Field of the Invention
This invention relates generally to mechanical fastening systems for attaching flexible sheets to track members, and more particularly to an improved clip track and clip member wherein the channel of the track is formed having an improved configuration including a base member with an angled bottom wall having fluted outer edges, angled side walls, and a durometer plastic insert or clip having rigid and semi-rigid sections.
Description of the Prior Art
It is well known in the art that various problems and difficulties are encountered in providing suitable means for securing and retaining a flexible sheet material or membrane to a substrate or support without either press-fitting or puncturing the sheet or membrane. For simplicity, the word "sheet" will be employed hereinafter to represent all types of sheets and membranes as known and used in the art such as, for example, cloth, canvas and plastic sheet materials.
With respect to specific prior art applications of mechanical fastening systems, one may refer to the following U.S. patents:
There is disclosed in U.S. Pat. No. 3,757,479 to Martinez a mirror comprising a frame with an external continuous groove having opposed side undercuts. A flexible strip presses a flexible reflective sheet into the grooves to hold the sheet in a fixed stretched condition on the frame of a smooth mirror surface. The flexible strip has an inverted V-shape with wings that can be pressed down and toward each other to enable the strip to enter the groove, wherein the groove is framed having an identical V-shaped cross-sectional configuration as the strip.
U.S. Pat. No. 3,805,873 to Bloomfield discloses a fastener for flexible covers utilizing a channel for receiving a locking member and for holding the cover in the channel when the flexible cover is under tension, the locking member being defined by a relatively flat bar. The internal configuration of the channel does not allow for extreme tensioning of the attached sheet or cover.
In U.S. Pat. No. 3,987,835 to Bloomfield there is disclosed a double-cord edge fastener for attaching canvas tarpaulin to structures. This device comprises a channel member fixed to a structure to be covered, and is used in cooperation with lock members having a pair of bead portions attached to the cover being used therewith.
There is disclosed in U.S. Pat. No. 4,107,826 to Tysdal a flexible covering anchor defined by a two-piece assembly that provides for attaching sheet material. The anchor comprises an elongated base member secured to a support and includes a channel longitudinally therealong for receiving a portion of the sheet material therein. A holding element is attached to the channel and is formed having a substantially S-shaped configuration so as to be positioned in and over the channel.
In U.S. Pat. No. 4,534,145 to Yang there is disclosed an attachment device for securing flexible sheets within a channel member via an insert member of a generally inverted V-shape, wherein the latter is made of a ductile but rigid material having a central longitudinal portion of reduced rigidity that serves to define two adjacent wing portions and permits the subsequent plastic deformation of the insert member into its installed shape after its insertion into the channel member.
There is further disclosed in U.S. Pat. No. 4,638,532 to Yang a mechanical fastening system for securing a flexible sheet within a channel member via an insert member, wherein the latter is made of flexible resilient material having a central longitudinal flex notch that serves to define two adjacent wing portions and permits a temporary elastic deformation of the insert member into an inverted V-shape for insertion of the insert member, together with the flexible sheet, into the channel member.